$("#datepicker").datepicker([$("#start_time").val(), $("#end_time").val()],
	function (a) {
		a.length > 1 ? ($("#start_time").val(a[0]), $("#end_time").val(a[1])) : ($("#start_time").val(a[0]), $("#end_time").val(a[0]))
	},
	{
		calendars: 2
	});
